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// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
//
// The inlining facility makes 2 passes: first caninl determines which
// functions are suitable for inlining, and for those that are it
// saves a copy of the body. Then inlcalls walks each function body to
// expand calls to inlinable functions.
//
// The debug['l'] flag controls the agressiveness. Note that main() swaps level 0 and 1,
// making 1 the default and -l disable. -ll and more is useful to flush out bugs.
// These additional levels (beyond -l) may be buggy and are not supported.
// 0: disabled
// 1: 40-nodes leaf functions, oneliners, lazy typechecking (default)
// 2: early typechecking of all imported bodies
// 3: allow variadic functions
// 4: allow non-leaf functions , (breaks runtime.Caller)
// 5: transitive inlining
//
// At some point this may get another default and become switch-offable with -N.
//
// The debug['m'] flag enables diagnostic output. a single -m is useful for verifying
// which calls get inlined or not, more is for debugging, and may go away at any point.
//
// TODO:
// - inline functions with ... args
// - handle T.meth(f()) with func f() (t T, arg, arg, )
package gc
import (
"cmd/internal/obj"
"fmt"
)
// Used by caninl.
// Used by inlcalls
// Used during inlsubst[list]
var inlfn *Node // function currently being inlined
var inlretlabel *Node // target of the goto substituted in place of a return
var inlretvars *NodeList // temp out variables
// Get the function's package. For ordinary functions it's on the ->sym, but for imported methods
// the ->sym can be re-used in the local package, so peel it off the receiver's type.
func fnpkg(fn *Node) *Pkg {
if fn.Type.Thistuple != 0 {
// method
rcvr := getthisx(fn.Type).Type.Type
if Isptr[rcvr.Etype] != 0 {
rcvr = rcvr.Type
}
if rcvr.Sym == nil {
Fatal("receiver with no sym: [%v] %v (%v)", Sconv(fn.Sym, 0), Nconv(fn, obj.FmtLong), Tconv(rcvr, 0))
}
return rcvr.Sym.Pkg
}
// non-method
return fn.Sym.Pkg
}
// Lazy typechecking of imported bodies. For local functions, caninl will set ->typecheck
// because they're a copy of an already checked body.
func typecheckinl(fn *Node) {
lno := int(setlineno(fn))
// typecheckinl is only for imported functions;
// their bodies may refer to unsafe as long as the package
// was marked safe during import (which was checked then).
// the ->inl of a local function has been typechecked before caninl copied it.
pkg := fnpkg(fn)
if pkg == localpkg || pkg == nil {
return // typecheckinl on local function
}
if Debug['m'] > 2 {
fmt.Printf("typecheck import [%v] %v { %v }\n", Sconv(fn.Sym, 0), Nconv(fn, obj.FmtLong), Hconv(fn.Inl, obj.FmtSharp))
}
save_safemode := safemode
safemode = 0
savefn := Curfn
Curfn = fn
typechecklist(fn.Inl, Etop)
Curfn = savefn
safemode = save_safemode
lineno = int32(lno)
}
// Caninl determines whether fn is inlineable.
// If so, caninl saves fn->nbody in fn->inl and substitutes it with a copy.
// fn and ->nbody will already have been typechecked.
func caninl(fn *Node) {
if fn.Op != ODCLFUNC {
Fatal("caninl %v", Nconv(fn, 0))
}
if fn.Nname == nil {
Fatal("caninl no nname %v", Nconv(fn, obj.FmtSign))
}
// If fn has no body (is defined outside of Go), cannot inline it.
if fn.Nbody == nil {
return
}
if fn.Typecheck == 0 {
Fatal("caninl on non-typechecked function %v", Nconv(fn, 0))
}
// can't handle ... args yet
if Debug['l'] < 3 {
for t := fn.Type.Type.Down.Down.Type; t != nil; t = t.Down {
if t.Isddd != 0 {
return
}
}
}
budget := 40 // allowed hairyness
if ishairylist(fn.Nbody, &budget) {
return
}
savefn := Curfn
Curfn = fn
fn.Nname.Inl = fn.Nbody
fn.Nbody = inlcopylist(fn.Nname.Inl)
fn.Nname.Inldcl = inlcopylist(fn.Nname.Defn.Dcl)
// hack, TODO, check for better way to link method nodes back to the thing with the ->inl
// this is so export can find the body of a method
fn.Type.Nname = fn.Nname
if Debug['m'] > 1 {
fmt.Printf("%v: can inline %v as: %v { %v }\n", fn.Line(), Nconv(fn.Nname, obj.FmtSharp), Tconv(fn.Type, obj.FmtSharp), Hconv(fn.Nname.Inl, obj.FmtSharp))
} else if Debug['m'] != 0 {
fmt.Printf("%v: can inline %v\n", fn.Line(), Nconv(fn.Nname, 0))
}
Curfn = savefn
}
// Look for anything we want to punt on.
func ishairylist(ll *NodeList, budget *int) bool {
for ; ll != nil; ll = ll.Next {
if ishairy(ll.N, budget) {
return true
}
}
return false
}
func ishairy(n *Node, budget *int) bool {
if n == nil {
return false
}
// Things that are too hairy, irrespective of the budget
switch n.Op {
case OCALL,
OCALLFUNC,
OCALLINTER,
OCALLMETH,
OPANIC,
ORECOVER:
if Debug['l'] < 4 {
return true
}
case OCLOSURE,
OCALLPART,
ORANGE,
OFOR,
OSELECT,
OSWITCH,
OPROC,
ODEFER,
ODCLTYPE, // can't print yet
ODCLCONST, // can't print yet
ORETJMP:
return true
}
(*budget)--
return *budget < 0 || ishairy(n.Left, budget) || ishairy(n.Right, budget) || ishairylist(n.List, budget) || ishairylist(n.Rlist, budget) || ishairylist(n.Ninit, budget) || ishairy(n.Ntest, budget) || ishairy(n.Nincr, budget) || ishairylist(n.Nbody, budget) || ishairylist(n.Nelse, budget)
}
// Inlcopy and inlcopylist recursively copy the body of a function.
// Any name-like node of non-local class is marked for re-export by adding it to
// the exportlist.
func inlcopylist(ll *NodeList) *NodeList {
l := (*NodeList)(nil)
for ; ll != nil; ll = ll.Next {
l = list(l, inlcopy(ll.N))
}
return l
}
func inlcopy(n *Node) *Node {
if n == nil {
return nil
}
switch n.Op {
case ONAME,
OTYPE,
OLITERAL:
return n
}
m := Nod(OXXX, nil, nil)
*m = *n
m.Inl = nil
m.Left = inlcopy(n.Left)
m.Right = inlcopy(n.Right)
m.List = inlcopylist(n.List)
m.Rlist = inlcopylist(n.Rlist)
m.Ninit = inlcopylist(n.Ninit)
m.Ntest = inlcopy(n.Ntest)
m.Nincr = inlcopy(n.Nincr)
m.Nbody = inlcopylist(n.Nbody)
m.Nelse = inlcopylist(n.Nelse)
return m
}
// Inlcalls/nodelist/node walks fn's statements and expressions and substitutes any
// calls made to inlineable functions. This is the external entry point.
func inlcalls(fn *Node) {
savefn := Curfn
Curfn = fn
inlnode(&fn)
if fn != Curfn {
Fatal("inlnode replaced curfn")
}
Curfn = savefn
}
// Turn an OINLCALL into a statement.
func inlconv2stmt(n *Node) {
n.Op = OBLOCK
// n->ninit stays
n.List = n.Nbody
n.Nbody = nil
n.Rlist = nil
}
// Turn an OINLCALL into a single valued expression.
func inlconv2expr(np **Node) {
n := *np
r := n.Rlist.N
addinit(&r, concat(n.Ninit, n.Nbody))
*np = r
}
// Turn the rlist (with the return values) of the OINLCALL in
// n into an expression list lumping the ninit and body
// containing the inlined statements on the first list element so
// order will be preserved Used in return, oas2func and call
// statements.
func inlconv2list(n *Node) *NodeList {
if n.Op != OINLCALL || n.Rlist == nil {
Fatal("inlconv2list %v\n", Nconv(n, obj.FmtSign))
}
l := n.Rlist
addinit(&l.N, concat(n.Ninit, n.Nbody))
return l
}
func inlnodelist(l *NodeList) {
for ; l != nil; l = l.Next {
inlnode(&l.N)
}
}
// inlnode recurses over the tree to find inlineable calls, which will
// be turned into OINLCALLs by mkinlcall. When the recursion comes
// back up will examine left, right, list, rlist, ninit, ntest, nincr,
// nbody and nelse and use one of the 4 inlconv/glue functions above
// to turn the OINLCALL into an expression, a statement, or patch it
// in to this nodes list or rlist as appropriate.
// NOTE it makes no sense to pass the glue functions down the
// recursion to the level where the OINLCALL gets created because they
// have to edit /this/ n, so you'd have to push that one down as well,
// but then you may as well do it here. so this is cleaner and
// shorter and less complicated.
func inlnode(np **Node) {
if *np == nil {
return
}
n := *np
switch n.Op {
// inhibit inlining of their argument
case ODEFER,
OPROC:
switch n.Left.Op {
case OCALLFUNC,
OCALLMETH:
n.Left.Etype = n.Op
}
fallthrough
// TODO do them here (or earlier),
// so escape analysis can avoid more heapmoves.
case OCLOSURE:
return
}
lno := int(setlineno(n))
inlnodelist(n.Ninit)
for l := n.Ninit; l != nil; l = l.Next {
if l.N.Op == OINLCALL {
inlconv2stmt(l.N)
}
}
inlnode(&n.Left)
if n.Left != nil && n.Left.Op == OINLCALL {
inlconv2expr(&n.Left)
}
inlnode(&n.Right)
if n.Right != nil && n.Right.Op == OINLCALL {
inlconv2expr(&n.Right)
}
inlnodelist(n.List)
switch n.Op {
case OBLOCK:
for l := n.List; l != nil; l = l.Next {
if l.N.Op == OINLCALL {
inlconv2stmt(l.N)
}
}
// if we just replaced arg in f(arg()) or return arg with an inlined call
// and arg returns multiple values, glue as list
case ORETURN,
OCALLFUNC,
OCALLMETH,
OCALLINTER,
OAPPEND,
OCOMPLEX:
if count(n.List) == 1 && n.List.N.Op == OINLCALL && count(n.List.N.Rlist) > 1 {
n.List = inlconv2list(n.List.N)
break
}
fallthrough
// fallthrough
default:
for l := n.List; l != nil; l = l.Next {
if l.N.Op == OINLCALL {
inlconv2expr(&l.N)
}
}
}
inlnodelist(n.Rlist)
switch n.Op {
case OAS2FUNC:
if n.Rlist.N.Op == OINLCALL {
n.Rlist = inlconv2list(n.Rlist.N)
n.Op = OAS2
n.Typecheck = 0
typecheck(np, Etop)
break
}
fallthrough
// fallthrough
default:
for l := n.Rlist; l != nil; l = l.Next {
if l.N.Op == OINLCALL {
inlconv2expr(&l.N)
}
}
}
inlnode(&n.Ntest)
if n.Ntest != nil && n.Ntest.Op == OINLCALL {
inlconv2expr(&n.Ntest)
}
inlnode(&n.Nincr)
if n.Nincr != nil && n.Nincr.Op == OINLCALL {
inlconv2stmt(n.Nincr)
}
inlnodelist(n.Nbody)
for l := n.Nbody; l != nil; l = l.Next {
if l.N.Op == OINLCALL {
inlconv2stmt(l.N)
}
}
inlnodelist(n.Nelse)
for l := n.Nelse; l != nil; l = l.Next {
if l.N.Op == OINLCALL {
inlconv2stmt(l.N)
}
}
// with all the branches out of the way, it is now time to
// transmogrify this node itself unless inhibited by the
// switch at the top of this function.
switch n.Op {
case OCALLFUNC,
OCALLMETH:
if n.Etype == OPROC || n.Etype == ODEFER {
return
}
}
switch n.Op {
case OCALLFUNC:
if Debug['m'] > 3 {
fmt.Printf("%v:call to func %v\n", n.Line(), Nconv(n.Left, obj.FmtSign))
}
if n.Left.Inl != nil { // normal case
mkinlcall(np, n.Left, int(n.Isddd))
} else if n.Left.Op == ONAME && n.Left.Left != nil && n.Left.Left.Op == OTYPE && n.Left.Right != nil && n.Left.Right.Op == ONAME { // methods called as functions
if n.Left.Sym.Def != nil {
mkinlcall(np, n.Left.Sym.Def, int(n.Isddd))
}
}
case OCALLMETH:
if Debug['m'] > 3 {
fmt.Printf("%v:call to meth %v\n", n.Line(), Nconv(n.Left.Right, obj.FmtLong))
}
// typecheck should have resolved ODOTMETH->type, whose nname points to the actual function.
if n.Left.Type == nil {
Fatal("no function type for [%p] %v\n", n.Left, Nconv(n.Left, obj.FmtSign))
}
if n.Left.Type.Nname == nil {
Fatal("no function definition for [%p] %v\n", n.Left.Type, Tconv(n.Left.Type, obj.FmtSign))
}
mkinlcall(np, n.Left.Type.Nname, int(n.Isddd))
}
lineno = int32(lno)
}
func mkinlcall(np **Node, fn *Node, isddd int) {
save_safemode := safemode
// imported functions may refer to unsafe as long as the
// package was marked safe during import (already checked).
pkg := fnpkg(fn)
if pkg != localpkg && pkg != nil {
safemode = 0
}
mkinlcall1(np, fn, isddd)
safemode = save_safemode
}
func tinlvar(t *Type) *Node {
if t.Nname != nil && !isblank(t.Nname) {
if t.Nname.Inlvar == nil {
Fatal("missing inlvar for %v\n", Nconv(t.Nname, 0))
}
return t.Nname.Inlvar
}
typecheck(&nblank, Erv|Easgn)
return nblank
}
var inlgen int
// if *np is a call, and fn is a function with an inlinable body, substitute *np with an OINLCALL.
// On return ninit has the parameter assignments, the nbody is the
// inlined function body and list, rlist contain the input, output
// parameters.
func mkinlcall1(np **Node, fn *Node, isddd int) {
// For variadic fn.
if fn.Inl == nil {
return
}
if fn == Curfn || fn.Defn == Curfn {
return
}
if Debug['l'] < 2 {
typecheckinl(fn)
}
n := *np
// Bingo, we have a function node, and it has an inlineable body
if Debug['m'] > 1 {
fmt.Printf("%v: inlining call to %v %v { %v }\n", n.Line(), Sconv(fn.Sym, 0), Tconv(fn.Type, obj.FmtSharp), Hconv(fn.Inl, obj.FmtSharp))
} else if Debug['m'] != 0 {
fmt.Printf("%v: inlining call to %v\n", n.Line(), Nconv(fn, 0))
}
if Debug['m'] > 2 {
fmt.Printf("%v: Before inlining: %v\n", n.Line(), Nconv(n, obj.FmtSign))
}
saveinlfn := inlfn
inlfn = fn
ninit := n.Ninit
//dumplist("ninit pre", ninit);
var dcl *NodeList
if fn.Defn != nil { // local function
dcl = fn.Inldcl // imported function
} else {
dcl = fn.Dcl
}
inlretvars = nil
i := 0
// Make temp names to use instead of the originals
for ll := dcl; ll != nil; ll = ll.Next {
if ll.N.Class == PPARAMOUT { // return values handled below.
continue
}
if ll.N.Op == ONAME {
ll.N.Inlvar = inlvar(ll.N)
// Typecheck because inlvar is not necessarily a function parameter.
typecheck(&ll.N.Inlvar, Erv)
if ll.N.Class&^PHEAP != PAUTO {
ninit = list(ninit, Nod(ODCL, ll.N.Inlvar, nil)) // otherwise gen won't emit the allocations for heapallocs
}
}
}
// temporaries for return values.
var m *Node
for t := getoutargx(fn.Type).Type; t != nil; t = t.Down {
if t != nil && t.Nname != nil && !isblank(t.Nname) {
m = inlvar(t.Nname)
typecheck(&m, Erv)
t.Nname.Inlvar = m
} else {
// anonymous return values, synthesize names for use in assignment that replaces return
m = retvar(t, i)
i++
}
ninit = list(ninit, Nod(ODCL, m, nil))
inlretvars = list(inlretvars, m)
}
// assign receiver.
var as *Node
if fn.Type.Thistuple != 0 && n.Left.Op == ODOTMETH {
// method call with a receiver.
t := getthisx(fn.Type).Type
if t != nil && t.Nname != nil && !isblank(t.Nname) && t.Nname.Inlvar == nil {
Fatal("missing inlvar for %v\n", Nconv(t.Nname, 0))
}
if n.Left.Left == nil {
Fatal("method call without receiver: %v", Nconv(n, obj.FmtSign))
}
if t == nil {
Fatal("method call unknown receiver type: %v", Nconv(n, obj.FmtSign))
}
as = Nod(OAS, tinlvar(t), n.Left.Left)
if as != nil {
typecheck(&as, Etop)
ninit = list(ninit, as)
}
}
// check if inlined function is variadic.
variadic := false
varargtype := (*Type)(nil)
varargcount := 0
for t := fn.Type.Type.Down.Down.Type; t != nil; t = t.Down {
if t.Isddd != 0 {
variadic = true
varargtype = t.Type
}
}
// but if argument is dotted too forget about variadicity.
if variadic && isddd != 0 {
variadic = false
}
// check if argument is actually a returned tuple from call.
multiret := 0
if n.List != nil && n.List.Next == nil {
switch n.List.N.Op {
case OCALL,
OCALLFUNC,
OCALLINTER,
OCALLMETH:
if n.List.N.Left.Type.Outtuple > 1 {
multiret = n.List.N.Left.Type.Outtuple - 1
}
}
}
if variadic {
varargcount = count(n.List) + multiret
if n.Left.Op != ODOTMETH {
varargcount -= fn.Type.Thistuple
}
varargcount -= fn.Type.Intuple - 1
}
// assign arguments to the parameters' temp names
as = Nod(OAS2, nil, nil)
as.Rlist = n.List
ll := n.List
// TODO: if len(nlist) == 1 but multiple args, check that n->list->n is a call?
if fn.Type.Thistuple != 0 && n.Left.Op != ODOTMETH {
// non-method call to method
if n.List == nil {
Fatal("non-method call to method without first arg: %v", Nconv(n, obj.FmtSign))
}
// append receiver inlvar to LHS.
t := getthisx(fn.Type).Type
if t != nil && t.Nname != nil && !isblank(t.Nname) && t.Nname.Inlvar == nil {
Fatal("missing inlvar for %v\n", Nconv(t.Nname, 0))
}
if t == nil {
Fatal("method call unknown receiver type: %v", Nconv(n, obj.FmtSign))
}
as.List = list(as.List, tinlvar(t))
ll = ll.Next // track argument count.
}
// append ordinary arguments to LHS.
chkargcount := n.List != nil && n.List.Next != nil
vararg := (*Node)(nil) // the slice argument to a variadic call
varargs := (*NodeList)(nil) // the list of LHS names to put in vararg.
if !chkargcount {
// 0 or 1 expression on RHS.
var i int
for t := getinargx(fn.Type).Type; t != nil; t = t.Down {
if variadic && t.Isddd != 0 {
vararg = tinlvar(t)
for i = 0; i < varargcount && ll != nil; i++ {
m = argvar(varargtype, i)
varargs = list(varargs, m)
as.List = list(as.List, m)
}
break
}
as.List = list(as.List, tinlvar(t))
}
} else {
// match arguments except final variadic (unless the call is dotted itself)
var t *Type
for t = getinargx(fn.Type).Type; t != nil; {
if ll == nil {
break
}
if variadic && t.Isddd != 0 {
break
}
as.List = list(as.List, tinlvar(t))
t = t.Down
ll = ll.Next
}
// match varargcount arguments with variadic parameters.
if variadic && t != nil && t.Isddd != 0 {
vararg = tinlvar(t)
var i int
for i = 0; i < varargcount && ll != nil; i++ {
m = argvar(varargtype, i)
varargs = list(varargs, m)
as.List = list(as.List, m)
ll = ll.Next
}
if i == varargcount {
t = t.Down
}
}
if ll != nil || t != nil {
Fatal("arg count mismatch: %v vs %v\n", Tconv(getinargx(fn.Type), obj.FmtSharp), Hconv(n.List, obj.FmtComma))
}
}
if as.Rlist != nil {
typecheck(&as, Etop)
ninit = list(ninit, as)
}
// turn the variadic args into a slice.
if variadic {
as = Nod(OAS, vararg, nil)
if varargcount == 0 {
as.Right = nodnil()
as.Right.Type = varargtype
} else {
vararrtype := typ(TARRAY)
vararrtype.Type = varargtype.Type
vararrtype.Bound = int64(varargcount)
as.Right = Nod(OCOMPLIT, nil, typenod(varargtype))
as.Right.List = varargs
as.Right = Nod(OSLICE, as.Right, Nod(OKEY, nil, nil))
}
typecheck(&as, Etop)
ninit = list(ninit, as)
}
// zero the outparams
for ll := inlretvars; ll != nil; ll = ll.Next {
as = Nod(OAS, ll.N, nil)
typecheck(&as, Etop)
ninit = list(ninit, as)
}
inlretlabel = newlabel_inl()
inlgen++
body := inlsubstlist(fn.Inl)
body = list(body, Nod(OGOTO, inlretlabel, nil)) // avoid 'not used' when function doesnt have return
body = list(body, Nod(OLABEL, inlretlabel, nil))
typechecklist(body, Etop)
//dumplist("ninit post", ninit);
call := Nod(OINLCALL, nil, nil)
call.Ninit = ninit
call.Nbody = body
call.Rlist = inlretvars
call.Type = n.Type
call.Typecheck = 1
setlno(call, int(n.Lineno))
//dumplist("call body", body);
*np = call
inlfn = saveinlfn
// transitive inlining
// TODO do this pre-expansion on fn->inl directly. requires
// either supporting exporting statemetns with complex ninits
// or saving inl and making inlinl
if Debug['l'] >= 5 {
body := fn.Inl
fn.Inl = nil // prevent infinite recursion
inlnodelist(call.Nbody)
for ll := call.Nbody; ll != nil; ll = ll.Next {
if ll.N.Op == OINLCALL {
inlconv2stmt(ll.N)
}
}
fn.Inl = body
}
if Debug['m'] > 2 {
fmt.Printf("%v: After inlining %v\n\n", n.Line(), Nconv(*np, obj.FmtSign))
}
}
// Every time we expand a function we generate a new set of tmpnames,
// PAUTO's in the calling functions, and link them off of the
// PPARAM's, PAUTOS and PPARAMOUTs of the called function.
func inlvar(var_ *Node) *Node {
if Debug['m'] > 3 {
fmt.Printf("inlvar %v\n", Nconv(var_, obj.FmtSign))
}
n := newname(var_.Sym)
n.Type = var_.Type
n.Class = PAUTO
n.Used = 1
n.Curfn = Curfn // the calling function, not the called one
n.Addrtaken = var_.Addrtaken
// Esc pass wont run if we're inlining into a iface wrapper.
// Luckily, we can steal the results from the target func.
// If inlining a function defined in another package after
// escape analysis is done, treat all local vars as escaping.
// See issue 9537.
if var_.Esc == EscHeap || (inl_nonlocal != 0 && var_.Op == ONAME) {
addrescapes(n)
}
Curfn.Dcl = list(Curfn.Dcl, n)
return n
}
// Synthesize a variable to store the inlined function's results in.
func retvar(t *Type, i int) *Node {
namebuf = fmt.Sprintf("~r%d", i)
n := newname(Lookup(namebuf))
n.Type = t.Type
n.Class = PAUTO
n.Used = 1
n.Curfn = Curfn // the calling function, not the called one
Curfn.Dcl = list(Curfn.Dcl, n)
return n
}
// Synthesize a variable to store the inlined function's arguments
// when they come from a multiple return call.
func argvar(t *Type, i int) *Node {
namebuf = fmt.Sprintf("~arg%d", i)
n := newname(Lookup(namebuf))
n.Type = t.Type
n.Class = PAUTO
n.Used = 1
n.Curfn = Curfn // the calling function, not the called one
Curfn.Dcl = list(Curfn.Dcl, n)
return n
}
var newlabel_inl_label int
func newlabel_inl() *Node {
newlabel_inl_label++
namebuf = fmt.Sprintf(".inlret%.6d", newlabel_inl_label)
n := newname(Lookup(namebuf))
n.Etype = 1 // flag 'safe' for escape analysis (no backjumps)
return n
}
// inlsubst and inlsubstlist recursively copy the body of the saved
// pristine ->inl body of the function while substituting references
// to input/output parameters with ones to the tmpnames, and
// substituting returns with assignments to the output.
func inlsubstlist(ll *NodeList) *NodeList {
l := (*NodeList)(nil)
for ; ll != nil; ll = ll.Next {
l = list(l, inlsubst(ll.N))
}
return l
}
func inlsubst(n *Node) *Node {
if n == nil {
return nil
}
switch n.Op {
case ONAME:
if n.Inlvar != nil { // These will be set during inlnode
if Debug['m'] > 2 {
fmt.Printf("substituting name %v -> %v\n", Nconv(n, obj.FmtSign), Nconv(n.Inlvar, obj.FmtSign))
}
return n.Inlvar
}
if Debug['m'] > 2 {
fmt.Printf("not substituting name %v\n", Nconv(n, obj.FmtSign))
}
return n
case OLITERAL,
OTYPE:
return n
// Since we don't handle bodies with closures, this return is guaranteed to belong to the current inlined function.
// dump("Return before substitution", n);
case ORETURN:
m := Nod(OGOTO, inlretlabel, nil)
m.Ninit = inlsubstlist(n.Ninit)
if inlretvars != nil && n.List != nil {
as := Nod(OAS2, nil, nil)
// shallow copy or OINLCALL->rlist will be the same list, and later walk and typecheck may clobber that.
for ll := inlretvars; ll != nil; ll = ll.Next {
as.List = list(as.List, ll.N)
}
as.Rlist = inlsubstlist(n.List)
typecheck(&as, Etop)
m.Ninit = list(m.Ninit, as)
}
typechecklist(m.Ninit, Etop)
typecheck(&m, Etop)
// dump("Return after substitution", m);
return m
case OGOTO,
OLABEL:
m := Nod(OXXX, nil, nil)
*m = *n
m.Ninit = nil
p := fmt.Sprintf("%s·%d", n.Left.Sym.Name, inlgen)
m.Left = newname(Lookup(p))
return m
}
m := Nod(OXXX, nil, nil)
*m = *n
m.Ninit = nil
if n.Op == OCLOSURE {
Fatal("cannot inline function containing closure: %v", Nconv(n, obj.FmtSign))
}
m.Left = inlsubst(n.Left)
m.Right = inlsubst(n.Right)
m.List = inlsubstlist(n.List)
m.Rlist = inlsubstlist(n.Rlist)
m.Ninit = concat(m.Ninit, inlsubstlist(n.Ninit))
m.Ntest = inlsubst(n.Ntest)
m.Nincr = inlsubst(n.Nincr)
m.Nbody = inlsubstlist(n.Nbody)
m.Nelse = inlsubstlist(n.Nelse)
return m
}
// Plaster over linenumbers
func setlnolist(ll *NodeList, lno int) {
for ; ll != nil; ll = ll.Next {
setlno(ll.N, lno)
}
}
func setlno(n *Node, lno int) {
if n == nil {
return
}
// don't clobber names, unless they're freshly synthesized
if n.Op != ONAME || n.Lineno == 0 {
n.Lineno = int32(lno)
}
setlno(n.Left, lno)
setlno(n.Right, lno)
setlnolist(n.List, lno)
setlnolist(n.Rlist, lno)
setlnolist(n.Ninit, lno)
setlno(n.Ntest, lno)
setlno(n.Nincr, lno)
setlnolist(n.Nbody, lno)
setlnolist(n.Nelse, lno)
}